Description: Science fiction portrays our Milky Way Galaxy as filled with habitable planets populated by advanced civilizations engaged in interstellar trade, conflict, super-technology, and romance. Back in our real universe, Earth-like planets and extraterrestrial life have proved elusive; not a microbe has been found. NASA's new space-borne Kepler telescope is finding the first Earth-like worlds around other stars. But what properties make a planet suitable for technological life? Could advanced life be more rare than we imagine?